AA Session Keys docs - small updates (#4451)

## Problem solved

Short description of the bug fixed or feature added

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---

## PR-Codex overview
This PR updates the user operation signing process and renames `smartWallet` to `wallet` for consistency.

### Detailed summary
- Updated user operation signing to be asynchronous
- Renamed `smartWallet` to `wallet` for consistency
- Changed `addAdmin` import to `addSessionKey`

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Author: edwardysun

apps/portal/src/app/connect/account-abstraction/permissions/page.mdx

@@ -66,8 +66,8 @@ import { addAdmin } from "thirdweb/extensions/erc4337";
 import { smartWallet } from "thirdweb/wallets";
 import { sendTransaction, getContract } from "thirdweb";
 
-const smartWallet = new smartWallet(config);
-const smartAccount = await smartWallet.connect({
+const wallet = new smartWallet(config);
+const smartAccount = await wallet.connect({
 	client,
 	personalAccount,
 });
@@ -134,7 +134,7 @@ const onClick = () => {
 			client,
 		}),
 		account: smartAccount,
-		sessionKeyAddress: "0x...", // the address of the new session key
+		sessionKeyAddress: "0x...", // the address of the account allowed to use the session key
 		permissions: {
 			approvedTargets: "*", // the addresses of allowed contracts, or '*' for any contract
 			nativeTokenLimitPerTransaction: 0.1, // the maximum amount of native token (in ETH) that the session key can spend per transaction
@@ -151,11 +151,11 @@ const onClick = () => {
 <TabsContent value="typescript">
 
 ```ts
-import { addAdmin } from "thirdweb/extensions/erc4337";
-import { smartWallet } from "thirdweb/wallets";
+import { addSessionKey } from "thirdweb/extensions/erc4337";
+import { wallet } from "thirdweb/wallets";
 import { sendTransaction, getContract } from "thirdweb";
 
-const smartWallet = new smartWallet(config);
+const wallet = new smartWallet(config);
 const smartAccount = await smartWallet.connect({
 	client,
 	personalAccount,

packages/thirdweb/src/wallets/smart/lib/userop.ts

@@ -486,9 +486,10 @@ async function populateUserOp_v0_6(args: {
  * ```ts
  * import { signUserOp } from "thirdweb/wallets/smart";
  *
- * const userOp = createUnsignedUserOp(...);
+ * const userOp = await createUnsignedUserOp(...);
  *
  * const signedUserOp = await signUserOp({
+ *  client,
  *  userOp,
  *  chain,
  *  adminAccount,